• 대한토목학회논문집
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• 제29권5A호
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• pp.447-456
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• 2009

연속경간 강합성 플레이트 거더 및 박스 거더 단면을 현 도로교설계기준의 허용응력설계법(ASD)과 AASHTO-LRFD 설계기준에 근거하여 최근 교량설계핵심기술연구단을 중심으로 제안된 하중저항계수설계법으로 설계하였다. 두 방법으로 설계된 강거더 단면의 강재량과 구조성능을 분석하였으며, 휨파괴에 대한 신뢰도해석을 수행하고 신뢰도지수를 비교 및 분석하였다. ASD법으로 설계 시에는 현 도로교설계기준에 규정된 DB-24 및 DL-24 설계활하중을, LRFD법으로 설계 시에는 최근 국내 통행차량 측정결과 통계에 근거하여 제안된 설계활하중을 적용하였다. 3경간 연속교의 경간비를 4:5:4로 가정하고 중앙부 최대경간장은 30~80 m를 고려하였다. 두 방법으로 설계된 강합성거더 단면의 휨파괴에 대한 신뢰도해석은 국내에서 생산된 16,000여 구조용 강재 표본의 항복강도 통계적 특성이 반영된 휨저항강도의 통계를 이용하여 수행하였다.

• 정보관리연구
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• 제24권1호
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• pp.1-20
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• 1993

한국통신(韓國通信) 연구개발단(硏究開發團)에서는 사내(社內) 각 연구부서(硏究部署)에서 발생하는 각종 최신 연구정보(硏究情報)의 원문(原文)을 축적(蓄積) 공동활용(共同活用)하기 위하여 한국통신연구정보관리(韓國通信硏究情報管理) 시스템(KTRIMS)을 개발(開發)하였으며, 본(本) 고(稿)에서는 KTRIMS의 구성(構成)과 특징(特徵)을 중심(中心)으로 기술(記述)하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.23-24
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• 2021

Since 2011, apartment houses account for about 41% of the fires in residential facilities for the past 10 years. Fire-resistant performance of fire doors is becoming more important to prevent the spread of fire in apartment houses. This research analyzed the structure of fire door through each 10 DB based on the quality inspection report of Continuous Acquisition & Life-cycle Support(CALS) from 2016 to 2020, which passed the fire performance test based on the laws and notices of domestic fire door. Therefore, based on the results of the analysis of DB in the future, we will conduct a study on structural improvement and addition for fireproof performance improvement of fire door.

• Nutrition Research and Practice
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• 제10권6호
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• pp.569-574
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• 2016

BACKGROUND/OBJECTIVES: We investigated the anti-osteoarthritic effects of deer bone extract on the gene expressions of matrix metalloproteinases (MMPs) and collagen type II (COL2) in interleukin-$1{\beta}$-induced osteoarthritis (OA) chondrocytes. MATERIALS/METHODS: Primary rabbit chondrocytes were treated as follows: CON (PBS treatment), NC (IL-$1{\beta}$ treatment), PC (IL-$1{\beta}+100{\mu}g/mL$ glucosamine sulphate/chondroitin sulphate mixture), and DB (IL-$1{\beta}+100{\mu}g/mL$ deer bone extract). RESULTS: The results of the cell viability assay indicated that deer bone extract at doses ranging from 100 to $500{\mu}g/mL$ inhibits cell death in chondrocytes induced by IL-$1{\beta}$. Deer bone extract was able to significantly recover the mRNA expression of COL2 that was down-regulated by IL-$1{\beta}$ (NC: 0.79 vs. DB: 0.87, P < 0.05) and significantly decrease the mRNA expression of MMP-3 (NC: 2.24 vs. DB: 1.75) and -13 (NC: 1.28 vs. DB: 0.89) in OA chondrocytes (P < 0.05).CONCLUSIONS: We concluded that deer bone extract induces accumulation of COL2 through the down-regulation of MMPs in IL-$1{\beta}$-induced OA chondrocytes. Our results suggest that deer bone extract, which contains various components related to OA, including chondroitin sulphate, may possess anti-osteoarthritic properties and be of value in inhibiting the pathogenesis of OA.

• Journal of Microbiology and Biotechnology
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• 제28권8호
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• pp.1247-1259
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• 2018

Raspberries are polyphenol-rich fruits with the potential to reduce the severity of the clinical signs associated with obesity, a phenomenon that may be related to changes in the gut microbiota. The aim of this study was to investigate the effect of raspberry supplementation on the fecal microbiota using an in vivo model of obesity. Obese diabetic db/db mice were used in this study and assigned to two experimental groups (with and without raspberry supplementation). Fecal samples were collected at the end of the supplementation period (8 weeks) and used for bacterial 16S rRNA gene profiling using a MiSeq instrument (Illumina). QIIME 1.8 was used to analyze the 16S data. Raspberry supplementation was associated with an increased abundance of Lachnospiraceae (p = 0.009), a very important group for gut health, and decreased abundances of Lactobacillus, Odoribacter, and the fiber degrader S24-7 family as well as unknown groups of Bacteroidales and Enterobacteriaceae (p < 0.05). These changes were enough to clearly differentiate bacterial communities accordingly to treatment, based on the analysis of UniFrac distance metrics. However, a predictive approach of functional profiles showed no difference between the treatment groups. Fecal metabolomic analysis provided critical information regarding the raspberry-supplemented group, whose relatively higher phytosterol concentrations may be relevant for the host health, considering the proven health benefits of these phytochemicals. Further studies are needed to investigate whether the observed differences in microbial communities (e.g., Lachnospiraceae) or metabolites relate to clinically significant differences that can prompt the use of raspberry extracts to help patients with obesity.

• Applied Microscopy
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• 제51권
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• pp.6.1-6.9
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• 2021

Histopathology is a well-established standard diagnosis employed for the majority of malignancies, including breast cancer. Nevertheless, despite training and standardization, it is considered operator-dependent and errors are still a concern. Fractal dimension analysis is a computational image processing technique that allows assessing the degree of complexity in patterns. We aimed here at providing a robust and easily attainable method for introducing computer-assisted techniques to histopathology laboratories. Slides from two databases were used: A) Breast Cancer Histopathological; and B) Grand Challenge on Breast Cancer Histology. Set A contained 2480 images from 24 patients with benign alterations, and 5429 images from 58 patients with breast cancer. Set B comprised 100 images of each type: normal tissue, benign alterations, in situ carcinoma, and invasive carcinoma. All images were analyzed with the FracLac algorithm in the ImageJ computational environment to yield the box count fractal dimension (Db) results. Images on set A on 40x magnification were statistically different (p = 0.0003), whereas images on 400x did not present differences in their means. On set B, the mean Db values presented promising statistical differences when comparing. Normal and/or benign images to in situ and/or invasive carcinoma (all p < 0.0001). Interestingly, there was no difference when comparing normal tissue to benign alterations. These data corroborate with previous work in which fractal analysis allowed differentiating malignancies. Computer-aided diagnosis algorithms may beneficiate from using Db data; specific Db cut-off values may yield ~ 99% specificity in diagnosing breast cancer. Furthermore, the fact that it allows assessing tissue complexity, this tool may be used to understand the progression of the histological alterations in cancer.

• 한국자원식물학회지
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• 제24권2호
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• pp.174-180
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• 2011

본 연구는 고비의 성엽으로부터 항산화 물질 추출과 항산화 활성을 증가시키기 위한 적정 추출 조건을 구명하기 위하여 시행하였다. 동결건조 한 다음 분쇄한 고비 성엽 1 g을 메탄올, 80% 에탄올, 물 등 3종류의 용매와 혼합한 다음 상온에서 침지, $60^{\circ}C$의 항온 수조에서 가열, 200 rpm에서 교반하여 6시간동안 추출하거나 42 kHz의 초음파 수조에서 15, 30, 45분 동안 추출하였다. 추출물은 여과한 다음 최종 볼륨을 50 mL로 정량하여 가용성고형분, 총 폴리페놀 및 총 플라보노의 함량을 구하였으며, 항산화활성은 0.15 mM의 DPPH와 7.4 mM의 ABTS radical 소거능으로 측정하였다. 고비 성엽 추출물의 항산화 효과를 증가시키기 위해서는 메탄올과 80% 에탄올을 용매로 사용하는 것이 효과적인 것으로 나타났다. 메탄올을 용매로 초음파 수조에서 15분 동안 추출했을 때 총 폴리페놀의 함량(45.15 $mg{\cdot}g^{-1}$ db)과 DPPH radical 소거활성($RC_{50}$=0.35 $mg{\cdot}mL^{-1}$)이 가장 우수하였으며, 총 플라보노이드의 함량은 메탄올을 용매로 상온침지 또는 가열추출하였을 때 (38.10~38.10 $mg{\cdot}g^{-1}$ db), ABTS radical 소거활성은 80% 에탄올을 용매로 상온침지 또는 가열추출하였을 때 가장 우수하였다($RC_{50}$=0.21~0.22 $mg{\cdot}mL^{-1}$). 연구의 결과, 초음파 수조를 이용한 추출은 노력과 시간을 절감할 수 있는 효율적인 추출방법으로 생각되었으며, 고비의 성엽은 메탄올을 용매로 15~30분 동안 초음파 수조에서 추출하는 것이 추출물의 다양한 항산화활성을 증가시키는데 가장 적합한 것으로 나타났다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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• pp.201-208
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• 2004

To substitute conventional reinforced-concrete bridge deck, glass composite precast bridge deck - Delta Deck/sup TM/, which possesses advantages of light weight, high strength, corrosion resistance and durability, is developed for the DB24 truck load. Pultruded composite bridge deck is designed and fabricated. To verify serviceability and structural safety, finite element analysis, structural testing such as flexural test, local fatigue test, flexural fatigue test and field tests are conducted. In this paper structural characteristics of developed deck and its field application in Korea is presented.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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• pp.113-120
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• 2005

To substitute conventional reinforced-concrete bridge deck glass composite precast bridge deck - Delta $Deck^{TM}$, which possesses advantages of light weight, high strength, corrosion resistance and durability, is developed for the DB24 truck load. Pultruded composite bridge deck is designed and fabricated. In this paper some field applications and field load test of developed composite deck bridge are presented.

• 기계와재료
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• 제24권1호
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• pp.72-79
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• 2012

최근 미국 멕시코만에서의 대형 오일 누출 사고에서 보듯이 에너지플랜트에서의 사고는 막대한 인명피해, 경제적 피해를 유발한다. 최근 플랜트 설계의 주요 관심사는 플랜트의 생애주기에서 사고에 의한 위험도(RISK)를 적정 수준 아래로 제어하는 것이다. 이를 위해 플랜트 설계 단계에서 필요한 정량적 위험도 분석(Qualitative Risk Assessment) 방법론을 개괄하였다. 아울러 QRA의 핵심이 되는 플랜트 기기 고장률 DB 구축의 필요성을 논하였다.